1. Who is “they”? Who said it’s the same people?
2. It’s not lol at “a very real part of their religious practices”. My understanding is that they have very strong minhagim about bonfires. And you are the one who is always so into keeping ones’ minhagim!
3. It doesn’t make them phonies at all. They want people to keep Shabbos. That doesn’t mean that they have to disrupt their minhagim for people to keep Shabbos. And in any case, these people aren’t keeping Shabbos anyhow. If they were, there wouldn’t be an issue.
I am not taking sides here. I am not qualified to. I just wish people could be “dan l’kaf zchus” and understand that there could be two sides to the issue (and that they are also not qualified to take sides).